The question asks us to identify the segment in the given sentence that contains a grammatical error. Let's carefully examine the sentence provided:

"Billionaire Philip is the owner of the luxury yacht Lionheart, which worth an estimated $150 million."

Understanding the Sentence Structure

The sentence describes Billionaire Philip and his luxury yacht, Lionheart. It uses a relative clause, introduced by "which", to provide additional information about the yacht.

• The main clause is "Billionaire Philip is the owner of the luxury yacht Lionheart".
• The relative clause is "which worth an estimated $150 million". This clause modifies "Lionheart".

Identifying the Grammatical Error

Let's look closely at the relative clause: "which worth an estimated $150 million." The word "worth" in this context describes the value of the yacht. While "worth" can be a noun or a verb in some contexts (e.g., "his net worth", "it is worth noting"), when indicating value as an adjective, it typically follows a form of the verb "to be".

For example:

• The painting is worth a lot of money.
• How much is your car worth?
• It was worth the effort.

In the sentence, "worth" is used directly after the relative pronoun "which". "Which" represents "the luxury yacht Lionheart". The structure "which worth" lacks the necessary linking verb (a form of "to be", like "is" or "was") to correctly express the value of the yacht. The correct phrasing should be "which is worth an estimated $150 million."

Therefore, the segment "which worth" contains the grammatical error.

Analyzing the Options

Let's evaluate each segment provided in the options:

1. Billionaire Philip is: This segment is grammatically correct. "Billionaire Philip" is the subject, and "is" is the verb connecting it to the rest of the sentence.

2. the owner of: This segment is also grammatically correct and functions as part of the predicate describing what Billionaire Philip is.

3. which worth: As explained above, this segment is grammatically incorrect because it is missing the linking verb "is" before "worth". The correct form is "which is worth".

4. an estimated $150 million: This segment is correct and provides the estimated value. "Estimated" acts as an adjective modifying "$150 million".

Based on the analysis, the segment "which worth" contains the grammatical error.

Explanation of 'Worth' Usage

The word 'worth' is commonly used as an adjective meaning 'having a value of' or 'important, good, or useful enough to justify (an action)'. When used to indicate monetary value, it typically follows a linking verb (most often 'be').

Correct examples:

• The house is worth $500,000.
• Is it worth buying?
• That information is worth knowing.

Incorrect example (like the sentence in question):

• It worth a lot. (Should be: It is worth a lot.)

Revision Table: Identifying Sentence Errors

Additional Information: Relative Clauses

A relative clause is a type of dependent clause that adds more information about a noun (the antecedent). It often begins with a relative pronoun like 'who', 'whom', 'whose', 'which', or 'that'.

• 'Which' is used to refer to things or animals.
• The relative pronoun can function as the subject, object, or possessive within the relative clause, or it can follow a preposition.
• In the sentence, "which worth...", 'which' refers to 'the luxury yacht Lionheart'. The intended structure is likely 'which is worth...', where 'is' is the verb of the relative clause and 'worth' is a predicative adjective. The absence of 'is' creates the grammatical error.